Column 1: Compound
Column 2: Oxidation state
Column 3: Type of linkage
Column 1Column 2Column 3(I)Na2S2O3(i)+5(P)S−O−S(II)Na2S4O6(ii)−2(Q)−S−S−(III)H2S2O7(iii)+6(R)−O−O−(IV)H2S2O8(iv)+4(S)S=S
The only correct combination for Marshall’s Acid.
(IV) (iii) (R)
Peroxydisulfuric acid, also known as Marshall's acid - is the inorganic compound with the chemical formula H2S2O8. It contains sulphur in its +6 oxidation state and a peroxide group - where the specific oxygen atoms have a (-1) oxidation state. The other oxygen atoms bear their usual (-2) oxidation state.
Salts of this acid are known as persulfates and are industrially important as powerful oxidizing agents.
The acid is prepared by the reaction of chlorosulfuric acid with hydrogen peroxide:
2ClSO3H+H2O2⟶H2S2O8+2HCl